-five or older, may have low t. so talk to your doctor about low t. hey, michael! [ male announcer ] and step out of the shadows. hi! how are you? [ male announcer ] learn more at isitlowt.com. [ laughs ] hey! >>> good morning and welcome to "morning joe." i hope you and your family are having a great holiday week. now, this hour, we're going to be revisiting some of our best interviews and conversations of the year. >> and we begin with a man who's been both a vocal and symbolic part of the debt discussion. the chairman of berkshire hathaway, warren buffett. he joined us on set along with carol lummis, who came out with the new book, "tap dancing to work: warren buffett on practically everything 1966 to 2012." a compilation about the oracle of omaha. >> what is the principle of warren buffett's life that keeps him who he is, but keeps him in his house and omaha. what's that thing in life that drove him in high school and drives him now? >> well, he does like to succeed, but money is nothing, absolutely nothing. he's always been driven and he got interested in invest, when he was -- well, his fir